In a large bowl, combine the warm milk, yeast, and a teaspoon of the sugar. Let it sit for 5 to 10 minutes until foamy.

Add the remaining sugar, melted butter, egg, vanilla, and salt. Stir to mix well.

Gradually add the flour, mixing until you have a soft dough. Knead for about 5 to 7 minutes until smooth and slightly tacky.

Place the dough in a lightly greased bowl, cover it with a kitchen towel or plastic wrap, and let it rise in a warm spot for 45 to 60 minutes, or until it doubles in size.

While the dough rises, melt the butter in a small saucepan over medium-low heat.

Stir in the brown sugar, heavy cream, honey or maple syrup, and vanilla. Cook for 2 to 3 minutes until smooth.

Pour this mixture into the bottom of a 6-quart slow cooker and sprinkle the chopped nuts over the caramel if using.

Turn the risen dough onto a floured surface and roll it into a rectangle about 12 x 18 inches.

Spread the softened butter on top of the dough.

Mix the brown sugar, cinnamon, and salt, then sprinkle this mixture evenly over the butter.

Roll the dough tightly into a log starting from one long side. Cut it into 10 to 12 equal pieces and place them cut-side up over the caramel.

Cover the slow cooker and let the buns rest for 15 to 20 minutes. Place a kitchen towel under the lid to absorb extra moisture.

Cook on HIGH for 1 hour 45 minutes to 2 hours, checking around 1 hour 30 minutes. The buns should be puffed and lightly golden.

Remove the insert, let the buns cool for 5 to 10 minutes, then invert onto a serving platter. The caramel will flow over the buns.